Intermittent Output on Rotel

[neddyboy]

I have a Rotel RA-931 that has recurring problems with output. The left channel will occasionally be inaudible when I turn it on, and will cut out or lose most of its volume while I'm listening.

The key symptom (I think): if I crank the volume it seems to "break through" and go back to normal volume. This problem is common to all the function inputs.

I don't have enough knowledge to start testing components, but if someone says "it's probably the output transistor" I can swap that out myself.

Thanks in advance...

[5th element]

I don't know why you've posted this in chip amps as I don't think the 931 is a chipamp.

Besides that however the problem to me sounds like a loose connection somewhere. This could be anything such as a bad/dry solder joint, a dying/dirty pot or a dirty switch etc.

[wintermute]

circuit diagram available here --> http://www.audio-circuit.dk/Schemati...931-int-tm.pdf 5th Element is right not a chipamp... I'd lean towards either the volume pot or the balance pot (simply because you said cranking the volume will cause it to "break through" , but could equally be a dry joint or loose connector and movement from cranking the volume pot might be enough to make the bad contact start conducting again.

Prodding the circuit board with something non conductive (plastic pen chopstick, etc) when it's playing up can help to narrow down where the problem is if it is a dry joint... depending on where you prod it might make it better or worse..... some contact cleaner sprayed in your volume/balance pots may help if it is a problem with those.

Tony.

[neddyboy]

I'm afraid I don't know the difference. Thanks for your patience and feedback.

[5th element]

Originally Posted by neddyboy

I'm afraid I don't know the difference. Thanks for your patience and feedback.

A chip amp is an integrated circuit that generally requires no additional active components to function.

Think of an opamp but able to deliver far more current and able to swing greater voltages.

A more traditional amplifier, otherwise known as a discrete amplifier, is built out of individual active components - usually transistors - with variations using other switching devices, such as MOSFETs or JFETS etc.